I was wondering if anyone has run into a similar problem. I have a 2012 C250 with audio 20 and installed two subwoofers and amp in the trunk keeping the stock head unit. As soon as everything was hooked up I lost my front two TPMS sensors. I ran the power wire for the amp through a rubber grommet in the firewall just behind the battery and ran the wire down the passenger side of the car all the way to the trunk. I know the amp is causing the issue because when I take the fuse out of the power wire my sensors come back on. I know the power wire is crossing a couple of wires for the TPMS in two different places. I have tried moving the wires away but it doesn't seem to help. Has anyone ran into this problem or is there another way to route the power wire so it doesn't interfere.

Does the 2012 C250 still have the 12v line into the right hand side of the trunk? If so, try connecting the amp and ONE sub (half the total max current of two subs) and see if the TPMS sensors work. Could be a work-around, although not a high-amperage solution.

The sensors work via RF so any kind of power wire near the receiver can interrupt that, I've seen it happen before.